<script type="text/javascript">
	var RecaptchaOptions = {
	theme : 'clean'
	};
 </script>
<?php
	define("RECAPTCHA_API_SERVER", "http://www.google.com/recaptcha/api");
	define("RECAPTCHA_API_SECURE_SERVER", "https://www.google.com/recaptcha/api");
	define("RECAPTCHA_VERIFY_SERVER", "www.google.com");

	function _recaptcha_qsencode ($data)
	{
		$req = "";
		foreach ( $data as $key => $value )
			$req .= $key . '=' . urlencode( stripslashes($value) ) . '&';

		// Cut the last '&'
		$req=substr($req,0,strlen($req)-1);
		return $req;
	}

	function _recaptcha_http_post($host, $path, $data, $port = 80)
	{

		$req = _recaptcha_qsencode ($data);

		$http_request  = "POST $path HTTP/1.0\r\n";
		$http_request .= "Host: $host\r\n";
		$http_request .= "Content-Type: application/x-www-form-urlencoded;\r\n";
		$http_request .= "Content-Length: " . strlen($req) . "\r\n";
		$http_request .= "User-Agent: reCAPTCHA/PHP\r\n";
		$http_request .= "\r\n";
		$http_request .= $req;

		$response = '';
		if( false == ( $fs = @fsockopen($host, $port, $errno, $errstr, 10) ) )
				die ('Could not open socket');

		fwrite($fs, $http_request);

		while ( !feof($fs) )
				$response .= fgets($fs, 1160); // One TCP-IP packet
		fclose($fs);
		$response = explode("\r\n\r\n", $response, 2);

		return $response;
	}

	function recaptcha_get_html ($pubkey, $error = null, $use_ssl = false)
	{
		if ($pubkey == null || $pubkey == '') {
			die ("To use reCAPTCHA you must get an API key from <a href='https://www.google.com/recaptcha/admin/create'>https://www.google.com/recaptcha/admin/create</a>");
		}
		
		if ($use_ssl) {
					$server = RECAPTCHA_API_SECURE_SERVER;
			} else {
					$server = RECAPTCHA_API_SERVER;
			}

			$errorpart = "";
			if ($error) {
			   $errorpart = "&amp;error=" . $error;
			}
			return '<script type="text/javascript" src="'. $server . '/challenge?k=' . $pubkey . $errorpart . '"></script>

		<noscript>
			<iframe src="'. $server . '/noscript?k=' . $pubkey . $errorpart . '" height="300" width="500" frameborder="0"></iframe><br/>
			<textarea name="recaptcha_challenge_field" rows="3" cols="40"></textarea>
			<input type="hidden" name="recaptcha_response_field" value="manual_challenge"/>
		</noscript>';
	}

	class ReCaptchaResponse
	{
		var $is_valid;
		var $error;
	}

	function recaptcha_check_answer ($privkey, $remoteip, $challenge, $response, $extra_params = array())
	{
		if ($privkey == null || $privkey == '')
			die ("To use reCAPTCHA you must get an API key from <a href='https://www.google.com/recaptcha/admin/create'>https://www.google.com/recaptcha/admin/create</a>");

		if ($remoteip == null || $remoteip == '')
			die ("For security reasons, you must pass the remote ip to reCAPTCHA");


		if ($challenge == null || strlen($challenge) == 0 || $response == null || strlen($response) == 0)
		{
			$recaptcha_response = new ReCaptchaResponse();
			$recaptcha_response->is_valid = false;
			$recaptcha_response->error = 'incorrect-captcha-sol';
			return $recaptcha_response;
		}

		$response = _recaptcha_http_post (RECAPTCHA_VERIFY_SERVER, "/recaptcha/api/verify",
										  array (
												 'privatekey' => $privkey,
												 'remoteip' => $remoteip,
												 'challenge' => $challenge,
												 'response' => $response
												 ) + $extra_params
										  );

		$answers = explode ("\n", $response [1]);
		$recaptcha_response = new ReCaptchaResponse();

		if (trim ($answers [0]) == 'true')
				$recaptcha_response->is_valid = true;
		else
		{
			$recaptcha_response->is_valid = false;
			$recaptcha_response->error = $answers [1];
		}
		return $recaptcha_response;
	}

	function recaptcha_get_signup_url ($domain = null, $appname = null) {
		return "https://www.google.com/recaptcha/admin/create?" .  _recaptcha_qsencode (array ('domains' => $domain, 'app' => $appname));
	}

	function _recaptcha_aes_pad($val) {
		$block_size = 16;
		$numpad = $block_size - (strlen ($val) % $block_size);
		return str_pad($val, strlen ($val) + $numpad, chr($numpad));
	}

	function _recaptcha_aes_encrypt($val,$ky) {
		if (! function_exists ("mcrypt_encrypt")) {
			die ("To use reCAPTCHA Mailhide, you need to have the mcrypt php module installed.");
		}
		$mode=MCRYPT_MODE_CBC;   
		$enc=MCRYPT_RIJNDAEL_128;
		$val=_recaptcha_aes_pad($val);
		return mcrypt_encrypt($enc, $ky, $val, $mode, "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0");
	}


	function _recaptcha_mailhide_urlbase64 ($x) {
		return strtr(base64_encode ($x), '+/', '-_');
	}

	/* gets the reCAPTCHA Mailhide url for a given email, public key and private key */
	function recaptcha_mailhide_url($pubkey, $privkey, $email) {
		if ($pubkey == '' || $pubkey == null || $privkey == "" || $privkey == null) {
			die ("To use reCAPTCHA Mailhide, you have to sign up for a public and private key, " .
				 "you can do so at <a href='http://www.google.com/recaptcha/mailhide/apikey'>http://www.google.com/recaptcha/mailhide/apikey</a>");
		}
		

		$ky = pack('H*', $privkey);
		$cryptmail = _recaptcha_aes_encrypt ($email, $ky);
		
		return "http://www.google.com/recaptcha/mailhide/d?k=" . $pubkey . "&c=" . _recaptcha_mailhide_urlbase64 ($cryptmail);
	}

	function _recaptcha_mailhide_email_parts ($email) {
		$arr = preg_split("/@/", $email );

		if (strlen ($arr[0]) <= 4) {
			$arr[0] = substr ($arr[0], 0, 1);
		} else if (strlen ($arr[0]) <= 6) {
			$arr[0] = substr ($arr[0], 0, 3);
		} else {
			$arr[0] = substr ($arr[0], 0, 4);
		}
		return $arr;
	}

	function recaptcha_mailhide_html($pubkey, $privkey, $email)
	{
		$emailparts = _recaptcha_mailhide_email_parts ($email);
		$url = recaptcha_mailhide_url ($pubkey, $privkey, $email);
		
		return htmlentities($emailparts[0]) . "<a href='" . htmlentities ($url) .
			"' onclick=\"window.open('" . htmlentities ($url) . "', '', 'toolbar=0,scrollbars=0,location=0,statusbar=0,menubar=0,resizable=0,width=500,height=300'); return false;\" title=\"Reveal this e-mail address\">...</a>@" . htmlentities ($emailparts [1]);

	}
?>
